Weather Tec 10-83 Impact sprinkler

I have a Weather Tec 10-83 impact sprinkler that is missing a nozzle. It is an oddball size and is fine thread. I have looked online and cant find any documentation of it. I am pretty sure that it came from an underground sprinkler system, as the drive arm is extremely short and looks to be the same size as a 1/2" impact. On Weather Tec's website there is a 10-80 impact and nozzle on it looks like it would work but it seems like you can only buy 1/2" and 3/4" nozzles. Driving to a dealer is not an option as the closest one to me is in Montana and I live in Alberta, Canada. Does anyone know how I could obtain one of these nozzles.